1. Field of the Invention
The present invention is directed to well operations systems and operations and to well servicing systems and operations; and, in certain particular aspects, to fault diagnosis and troubleshooting of such systems and operations, particularly, regarding non-downhole apparatuses.
2. Description of Related Art
The prior art discloses a wide variety of well servicing systems and operations; for example, and not by way of limitation, the systems, devices, apparatuses, and methods disclosed in U.S. Pat. Nos. 4,591,006; 5,988,299; 5,711,382; 6,003,598; 6,377,189; 6,907,375 and in pending U.S. application Ser. No. 10/929,285 filed Aug. 30, 2004, all of said patents and application incorporated fully herein for all purposes.
Once a well has been completed and is operating to extract material from within the earth—e.g. petroleum, gas, hydrocarbons, water or other fluid—various service operations are periodically performed to maintain the well which utilize above-ground devices, systems, and apparatuses. Such service operations may include e.g.: acidizing, fracturing, pumping sand, replacing worn parts such as a pump, sucker rods, inner tubing, and packer glands; pumping chemical treatments or hot oil down into the well bore; tubing services; workovers; milling; setting packers; plug and abandonment operations; and pouring cement into the well bore to partially close off a portion of the well (or to shut it down entirely). Maintenance or service operations can be performed by a well servicing rig, mobile rig, or by a workover rig, swab rig, or a service vehicle having special servicing equipment.
One particular prior art system useful in well servicing operations, provided by National Oilwell Varco is the KINETIC ENERGY CONTROL SYSTEM (described, e.g. in National Oilwell Varco Document No. SO 22277-0501-OPM-001; pp. 4-31) that has PLC-based instrumentation and controls that increase the functionality of a rig's engine, drawworks clutch and brakes. With such systems there is electric rather than hydraulic/pneumatic operation of the drawworks, engine, and brakes which requires less physical exertion by an operator. The system provides alarms and monitoring of selected rig parameters to enable the operator to make more informed decisions. Stainless steel NEMA 4× enclosures are used which are suitable for hazardous area use (where necessary) and resilient mountings protect against shock and vibration.
One prior art version of the KECS system, the KECS—0002 version, provides a fault finding procedure with two basic steps: (1) basic inspection and testing of components and wiring and (2) software interrogation which requires plugging in a laptop computer into a system's PLC (“programmable logic controller”) and interrogating the software. In certain aspects, the first step is done by a competent electrician. The second step is done, e.g., by a software engineer with knowledge of the system and the software code.
The present inventors have discovered that it would be beneficial to use such a system for diagnosis and fault finding without requiring an operator's knowledge of the software code and without actually accessing that code.